I kinda feel you keep Smoak for now regardless of a rebuild or not, unless someone really blows you away. If he can build on this season and demonstrate it during the first half next year, you'll get a LOT more next year.
There would be value in giving Biagini some more innings to close out the year too. Also, moving Estrada's salary might make it easier to take on salary for someone controllable next year.
I don't think we'd get much for Estrada. Most we could probably hope for would be a long shot wildcard guy, plus salary relief. Maybe someone like Starling, or Billy Burns.